Improvement in plows



AIINIClED STATES PMPENT OFFICE.

. BYRON C. BRADLEY, OF CHICAGO, ILLINOIS.

IMPROVEMENT IN PLOWS.

Specification forming part of Letters Patent No. 154,119, dated August 18, 1874; application filed i Y June 12, 1874.

To all whom it may concern:

Be it known that I, BYRON C. BRADLEY, of the city of Chicago, in the county of Cook and State of Illinois, have invented anew and useful Improvement in Plows, of which Vthe following is a full description, reference being had to the accompanying drawings, in Which- Figure l is a side elevation 5 Fig. 2, a top view of the mold-board and share; Fig. 3, an illustration of my way of determining the form of various sizes.

The object of my invention is to construct a plow which will scour readily, and which will pass through the earth and turn the furrow more easily than those now in use; and it consists in giving the share and Inold-board a convex form, the crown-line of the convexity being a curved line, preferably the arc of a circle, extending from the delivery-point of the mold-board to a point in the cutting-edge of the share, the distance of this point'from the land-side being equal to one-third of the Whole length of the cutting-edge.

In the drawings, a represents the share; b, the mold-board; c, the crown-line of the convexity of the share and mold-board. One end of this crown-line is at d, thedelivery-point of the mold-board. The other end is at ein the cutting-edge, and this line is the arc of a circle, struck while the parts are flat, as shown in Fig. 3. The share and mold-board are both made convex and adapted to tit the other parts, and the top of the mold-boardis to be curved, as usual. The point of the plow is not convex, but has the usual form.

The drawin gs represent a fourteen-inch plow.

Fig. 3 is on a larger scale than the others, and shows my plan for determining the outlines of the share and mold-board, and the crown-line of the convexity.

I find Ythat the angle which the cutting-edge of the share forms with the landside should vary with varying sizes, and that for a fourteen-inch plow this angle should be forty-five degrees, or about that. The delivery-point d should be about an inch and a half over or beyond a line drawn through the heel h parallel with the land-side.

fis the point where the cutting-edge continued would cross the land-side.

The distance from el to f in a fourteen-inch plow should be thirty-two inches. The same line in an eight-inch plow would be twentyve inches.

In Fig. 3 the heavy outer lines represent the outlines of a share, point, and .mold-board of a fourteen-inch plow, the parts lying fiat. The line d e is the crown-line ofthe convexity of the share and moldboard.

t' is the delivery-point of an eight-inch plow. In a circle passing through these two points will be found the delivery-points of the moldboards of plows of other sizes; for example, the delivery-point of a twenty-inch plow would be at g.

To determine the location of the heel of the cutting-edge of any other given size, I strike a circle, passing through h, the radius being fifty-six inches, so that the chord h f, continued, will subtend an arc equal to one-fourth of a circle, the line hfbeing at an angle of forty-live degreeswith land-side, or with the line 1' parallel with the land-side, the center of the circle being in the liner extended. The heel of the cutting-edge of the share of a twenty-inch plow will be at k, the heel of an eight-inch plow at s. The line n shows the line of the cutting-edge of the share of a sixinch plow. The interior dotted lines represent an eight-inch plow.

The angles of the cutting-edges may be varied from those given; but having determined in which size the cuttin g-ed ge of the share shall be at an angle of forty-live degrees with the land-side, the angles of the cutting-edges of other sizes can be determined as above.

By adopting substantially the rules given the several parts of the plow will be duly proportioned in plows of different sizes.

I am aware that plows have been made with a convex mold-board and share but in all cases the crown-line of the convexity of the Vshare and lower part of the mold-board. has

been in a line parallel with the land-side and along the center of the plow, commencing at the center of the cutting-edge of the share. When so formed the earth has a tendency to pass up over the plow in lines parallel with the land-side, and the furrow is crowded and forced over by-the curvature given to the upper part of the mold-board.

When the form is given which I have deparallel with the land-side.

scribedthat is, when the crown-line of the convexity extends from the delivery-point dto the point e in the cutting-edge of the share in a curvethe earth, as the plow moves along, passes up over the plow in lines parallel with the crown-lille c of the convexity, instead of The curved lines in Figs. 1 and 2 indicate the direction of the earth.

For different kinds of ploWs the dimensions and angles given may be somewhat varied. Those given will be found suitable for stubble-plows.

The location and curvature of the crownline of the eonvexity can be slightly varied Without very materially injuring the plow or Y, changing the result; but my experiments lead me to believe that the location and curvature described are the best.

I do not claim, broadly, a plow having a convex mold-board and share; but

What I do claim as new, and desire to secure by Letters Patent, is `as follows:

'A plow having -a convex mold-board and share, the crown point or line of convexity extending from a point in the cutting-edge of the share to the delivery-point of the moldboard upon the line c, substantially as and for the purpose specified.

BYRON C. BRADLEY. Witnesses:

E. A. WEST, O. W. BOND. 

